Sorted:

Cacti system handle data collection at varying time intervals?

What scale of network environment is the Cacti system suitable for?

Cacti system support scheduled tasks and automation operations

How is the reporting function of the Cacti system implemented?

What is the role of the Cacti system in troubleshooting?

In what ways can Nagios automatically discover new devices?

Different alert notification methods supported by Nagios?

What common monitoring metrics are supported by Zabbix?

How to create users and permissions in Nagios?

How does Nagios manage the historical logs of monitoring events?